Slide projector for slides in a magazine or in a separate container



Feb. 23, 1965 H MULCH 3,170,370

SLIDE PROJECTOR FOR SLIDES IN A MAGAZINE OR IN A SEPARATE CONTAINER Filed Aug. 23, 1962 5 Sheets-Sheet 1 IN VE N TOR HANS MULCH Feb. 23, 1965 u CH 3,170,370

H. M L SLIDE PROJECTOR FOR SLIDES IN A MAGAZINE OR IN A SEPARATE CONTAINER Filed Aug. 23, 1962 5 Sheets-Sheet 2 Fig. 2

INVENTUR HANS MULCH Af/omeys Feb. 23, 1965 H, MULCH sum: PROJECTOR FOR SLIDES IN A MAGAZINE OR IN A SEPARATE CONTAINER 5 Sheets-Sheet 3 Filed Aug. 23, 1962 Fig. 4

nv VENTOR HA N5 MULCH Alforney;

Feb. 23, 1965 H. MULCH 3,170,370

SLIDE PROJECTOR FOR SLIDES IN A MAGAZINE OR IN A SEPARATE CONTAINER Filed Aug. 23, 1962 5 SheetsSheet 4 Fig. 56 Fig. 517 Fig. 5C

INVENTOR HANS MULCH BY Feb, 23, 1965 H. MULCH 3,170,370 7 SLIDE PROJECTOR FOR SLIDES IN A MAGAZINE Q OR m A SEPARATE CONTAINER Filed Aug. 23, 1962 5 Sheets-Sheet 5 46 46 48 J 9- 7 48 Fig. 8a

INVENTOR HANS MULCH Affamevs resilient means.

'(Lahn), Germany Filed Aug. 23, 1962, Ser. No. 218,954 Claims priority,'application Germany, Sept. 2, 1961,

. L 39,925 Claims. (Cl. 8828) The present invention relates to a slide projector, more particularly, to a slideprojector having a slide-changing mechanism and a magazine-advancing mechanism wherein slides may be automatically projected from either a slide magazine or a slide-storage compartment positioned on a guideway in the projector.

For use in slide projectors slide magazines are commonly used wherein the magazines are divided into a plurality of compartments and each compartment loosely retains a slide therein. The magazine is then placed upon the guideway in a slide projector and the slidechanging mechanism automatically takes slides from the magazine, moves them into the projecting position and returns the slides to their respective compartments in the magazine after projection thereof. One disadvantage of such slide magazines, however, is that the slides must be individually inserted into the slide compartments and that new magazines are required to house additional slides. The disadvantage of a slide magazine as described above is eliminated in those slide projectors which are constructed to receive slide storage containers. In these containers the slides are positioned next to each other and usually urged against a fixed Wall of the container by The container is generally divided into two sections with the slides being removed from one section for projection andthen returned to the other section .after the projection thereof.

Theme of such slide-storage containers has the advantage that it is not necessary to individually position the slides in compartments and that a pile ofslides may merely be positioned within the container and the container is ready for insertion into the slide projector.

It is therefore the principal object of the present invention to provide a novel and improved'slide projector.

It is an additional object of the present invention to provide a slide projector which can automatically project slides from either a slide magazine or a slide-storage container positioned on the guideway of the slide projector.

The slide projector of the present invention essentially comprises, in addition to the conventional slide-changing mechanism and magazine-advancing structure, a guideway which isadapted to receive either a slide magazine or a slide-storage container. The guideway is provided with structureto properly position the slide-storage container thereon and to lock the container in this position during the time that slides are projected therefrom. The slide-storage container is provided with a transverse dividing wall with the slides to be projected positioned on one side of the wall andthe slides returned to the other side of the wall after the projection thereof. An adapting structure is provided which cooperates with both the slidechanging mechanism and the slide-storage container for removing the slides from one side of the dividing wall and'for returning the slides to theother side of the dividing Wall after the projection thereof.-. The container is further, provided with resilient end' walls'which continuously urge the slides on both sides. of the dividing wall I against the wall.

In order to transfer the slides from one side of the United States Patent 0 partment in cooperation with the slide changing mechanism. ;In addition tobeing advanced the slide magazine 3,170,370 Patented Feb. 23, 1965 slide-storage container to the other side thereof while projecting the slides, a resilient structure must be provided on the container. Inone modification the entire slide-storage container is free to move in a longitudinal 1 direction a limited distance each time a slide is returned to the other side of the dividing wall. i

In another modification, the dividing wall itself is resiliently mounted so as tobe displaceable longitudinally of the slide container when the slide is being returned after projection thereof. Anadditional modification comprises resiliently supporting the slide-changing mechanism or constructing the slide-changing mechanism so tion and showing the manner in which' a. slide storage container or a slide magazine is insertedinto the guideway thereof;

FIGURE 2 is a longitudinal sectional view of the slide storage container in the present invention;

vFIGURE 3 is a top" plan view of the. container of FIGURE 2; j a

FIGURE 4 is a longitudinal sectional view of a slide container having a movable dividing wall;.

FIGURE 5 is a transverse sectional view of a slide container taken along the line A-A of FIGURE 4; FIGURES 6a, 6b and 6c are top plan views of a portion of a slide container showing the slide changing mech- I anism in various operational positions;

" FIGURES 7, 8a and. 8b are side elevational views of portions of a slide container showing various operational 7 positions of a slide changing mechanism having one gripper arm pivotally mounted; and

FIGURE.9 is an overall perspective view of a portion of a slide changing mechanism having several movable gripper' arms.

Returning now to the drawings wherein like reference symbols indicate the same parts throughout the various of the slide magazine 3 and are progressively raised by the .cam' surface 8 as the slide magazine is advanced. along the guideway. When each slide is raised to itsuppermost position it is then gripped by a slide changing mechanism comprising a slider..9 and having gripping arms 10 and 11. The gripping arm 10 urges the slide transversely from the slide magazine a'nd into the projecting position within the projector. After. projection thereof the gripping arm 11 then pushes the slide back to its compartment in the ..slide magazine.

The slide changing mechanism is actuated manually by a handle 13 or automatically by a motor which may be controlled by a remote control switch'14 or an operating button 15 on the casingfof the slide projector.

After each slide changing cycle then theslide is returned to its compartment after projectionthereof, the

gear 6 is rotatedby conventionalstructure which is not illustrated in'the drawings and the magazine is advanced by a distance sufiicient to position the next successive com- 3 may also be moved in the reverse direction by means of the knurled knob 16 projecting from the casing. As a result any slide in the slide magazine may be selectively projected and it is not necessary to project the slides in the sequence in which they are positioned in the slide magazme.

The guideway 2 is provided with a bottom wall 17 having a pair of spaced slots 18 therein into which are inserted tabs 19 which project downwardly from the bottom of the slide storage container. Thus, when the container is positioned upon the bottom 17 the-cooperating slots and tabs securely hold the container in position in the guideway. 1

The container is provided with a lateral wall 21 and a transversely extending dividing wall 22 positioned in the center of the container and thus forming two sections or compartments and 23 of the container. The section 20 holds the pile of slides 24 which are to be projected and the section 23 receives the slides 25 after they have been projected. These slides are urged against the dividing wall 22 by pressure plates 26 and 27, respectively, which are slidably mounted on a rod 28 and are interconnected by a spring 29.

The width of the slide storage container 4 is less than the width of the slide magazine 3 by the width of the rack gear 5 so as to prevent any contact of the slide storage container by the magazine advancing gear 6. The slots 18 and the tabs 19 are so positioned so that the slide storage container is retained in the guideway in such a position that it is not contacted by the gear 6.

The bottom wall 31 of the slide storage container is positioned at such a height (as may be seen in FIG. 2 and FIG. 5) that the uppermost surface of this bottom wall is at substantially the same height as the maximum height of the cam surface 8. However, a slot 30 is provided in the bottom wall 31 to receive the cam surface 8 so that this cam surface does not operatively contribute in any way to the slide changing operation with respect to a slide storage container. By positioning the bottom wall 31 at this height the slides can be moved into the slide projector in the same manner as they are moved from a slide magazine without any necessity for compensating in differences of heights between the bottoms of the slides.

In order that the slider 9 may remove a slide from one side of the dividing wall 22 and return this slide to the other side of the dividing wall after projection thereof structure is provided which operatively cooperates with the slide changing mechanism. This is accomplished by movably mounting the dividing wall 22 upon the rod 28 so that it is displaceable longitudinally of the container under the action of a spring 32 and this movement is limited by stops 33 as shown in FIGURE 4. A curved leaf spring 34 is mounted on one side of the wall 22 and a leaf spring 35 mounted on the other side thereof with 'both springs extending a short distance above the top edge of the wall 22 so as to form paths of movement for the slider 9 in a manner to be presently described. These springs 34 and 35 are engaged by a skid 36 extending from the bottom of the gripper arm 10, and this skid dependent upon the direction. of movement of the slider 9, moves along the guide path 37 formed between the leaf springs 34 and 35 or along the exterior side of the curved leaf spring 34. A cam surface 38 is provided on the surface of the dividing wall 22 facing the pressure plate 27.

There is a blade 39 on the inner edgeof the gripper arm 10 tov facilitate gripping of the slides when moving a slide from the container into the projecting position. The front edge 40 of the curved leaf spring 34 and the edge 41 of a side wall 42 form an aperture the width of which corresponds to the thickness of a slide as may be clearly seen in FIGURE 6b.

The operation of the slide projector of the present invention where a slide storage container is positioned upon the guideway is carried out in the following manner: By manually manipulating the handle 13 the slider 9 is moved into the casing of the slide projector so that the gripper arms 10 and 11 are no longer in the guideway 2 and the guideway 2 is thus open. The slide storage container 4 is then inserted into the guideway 2 from above as indicated by the arrow B in FIGURE 1. The tabs 19 on the bottom of the container engage with the slots 18 to hold the container in position. The leading slide in the delivery pile of'slides 24 which is against the dividing wall 22 is positioned directly in front of the slot 12 at the height which the slide will occupy when it is in the projecting position. The slide changing mechanism is then actuated by the operator so that the slider 9 is returned to its outermost or gripping position as shown in FIGURE 1, and the position of the slider with respect to the slides is shown in FIGURE 6a.

When the slide changing mechanism is next actuated, either manually or automatically, the blade 39 on the gripper arm 10 will engage the slide in front of the slot 12 and move it into the slide projecting position. During this movement of the slider 9 the skid 36 will be guided in the path 37 and will press the curved end 40 of the leaf spring 34 outwardly as the skid passes over the side of the container.

After projection of the slide the gripper arm 11 then pushes the slide toward the guideway. The skid 36 will contact the curved end 40 of the leaf spring 34, but since the slider can move only straight forward the dividing wall 22 and the slides 24 will be moved to the left as shown in FIGURE 6a through 60, since the wall 22 is resiliently mounted on the rod 28. Thus, the return slide Will not enter the slot formed by the edge 41 of the side wall 42 and the end of the leaf spring 40 but will slide along the outer surface of the leaf spring 34 and then along the cam surface 38. In the last phase of its return movement the slide will push back the resilient pressure plate 27 and the storage pile of slides 25. The cam surface 38 is so constructed that the slides positioned in compartment 23 are parallel with respect to the pressure plate 27. Thus, sufficient space is left between the front slide of the pile of slides 25 and the dividing wall 22 so that the return slide may be easily pushed into position by the slider 9.

After the skid 36 has passed the leaf spring 34 on its return movement the dividing wall 22 can be returned into its initial position as in FIGURE 6a. Now the blade 39 of thegripper arm 10 is against positioned in front of the next slide which is to be projected.

The arrangement may be modified by constructing the slide storage container in such a manner that the entire container moves in order to obtain the necessary displacement to permit the return slide to be delivered to the stack of slides which have already been projected. As may be seen in FIGURE 2 the end surfaces of the container are provided with leaf springs 43 and 44 which have extensions 19A which in turn are inserted into slots 18A for orienting the container. The slots 18A, however, are formed of a sutficient width to permit a movement of the slide container in the longitudinal direction. In order to minimize friction during this movement of the container rolls 2a and 2b are mounted just below the bottom surface 17 of the guideway 2 for supporting the slide container.

The dividing wall 22 in this modification functions in the same manner as previously described. In the operation of this modification the entire container moves, whereas as previously described only the dividing Wall moved to accommodate the returned slides.

As can be also seen from FIGURE 2 the side wall 42 is adjustably mounted so that the slot through which the slides are passed when moving into the projecting position can be adjusted to any size and thus can accommodate slides of various thickness. 1

A further modification of the invention is shown in FIGURES 7, 8a and 8b, wherein the slide container is stationary but parts of the slider 9 are movable. As may be seen in FIGURE 7 the slider 9 comprises a gripper arm 45 which is pivotally mounted about the shaft 46 which in turn is a component of the slider. The lower end of .the gripper arm 45 is provided with a projection 47 which can be moved laterally and returned to its regular position under the action of a spring 34. The positions of the gripper arm 45 are indicated in FIGURE 7. Thus, when the slider is moving to' return a slide in the container the projection 47 moves against theouter face of the curved leaf spring 34 as shown in FIGURE 7.

As is shown in FIGURES 8a and 8b a fork 49 can be used instead of the projection 47. -The operation of this structure is the same as the slider shown in FIG- URE 7.

Since it is possible that the movable gripper arm as illustrated in FIGURES 7, 8a, and 8b may cause difiiculties when a slide magazine is used in the projector instead of the slide container a further modification is shown in FIGURE 9. In this modification two gripper arms 50 and 51 are provided with the gripper arm 50 being used for a slide magazine and the gripper arm 51 for a slide container.

Both gripper arms are pivotally mounted about the shaft 52 on a slider 53. In an non-engaged position they may be retained in their uppermost position by a spring lock 54. The gripper arm 50 is pivotable in only one plane which is perpendicular with respect to the optical axis of the slide projector. The gripper arm 51, however, which corresponds to the gripper arm 45, shown in FIGURES 7, 8a, and 8b, is pivotable in two planes.

Thus, it can be seen that the present invention provides a slide projector which can be readily used to project slides delivered either from a compartrnented slide magazine or from a slide container. The construction of the slide projector is such that no adaptation is needed by the operator when changing from the use ofa slide magazine to a slide storage container or viceversa. With this invention the versatility of a slide projector is considerably increased.

It will be understood that this invention is susceptible to further modification and, accordingly, it is desired to comprehend such modifications within this invention as may fall within the scope of the appended claims.

What is claimed is:

1. A slide projector comprising a casing, means in said casing defining a guideway for a slide magazine having slide compartments therein with slides being retained in said compartments, a slide-changing mechanism for transfen-ing slides from said magazine to the projecting position and returning the slides to their respective compartments in the magazine, magazine-advancing means for advancing said slide magazine in response to the slide-changing position, said guideway having a slot in the base thereof for receiving a tab of a slide-storage container wherein the slides are held against each other whereby said container is locked in position on said guideway, there being a transverse dividing wall in the center of said slide storage container, means in said storage container cooperating with said slide changing mechanism for removing slides through a slot from one side of said dividing wall and for returning the slides after projection thereof to the other side of the said dividing wall, said last-named means comprising a leaf spring secured at one end to said dividing wall and extending therealong with its other end curved toward and terminating at said slot, and the upper edge of said leaf spring extending above and in spaced relation to the upper edge of the dividing wall to provide a guiding edge for said slide changing mechanism.

2. A slide projector comprising a casing, means in said casing defining a guideway for a slide magazine, means on said guideway for holding in position thereon a slidestorage container wherein the slides are held against each other, there being a transverse dividing wall in the center of said slide-storage container, a reciprocating slide-changing mechanism mounted insaid casing for transferring :slides from said slide-storage containerqto, the projecting position and returning the slides to the storage container,

means operatively cooperating; with said slide-changing mechanism and said slide-storage container held in position on said guideway for removing slides from one side of said dividing wall and for returning the slides after the upper edge of the said wall thereby providing a guiding edge for said slide-changing mechanism, and resilient means on said slide-storage container for urging the slides on both sides of said dividing wall thereagainst.

3. A slide projector comprising a casing, means in said casing defining a guideway for a slide magazine, means on said guideway for holding in position thereon a slidestorage container wherein the slides are held against each other, there being a transverse dividing wall in the center of said slide-storage container, a reciprocating slide-changing mechanism mounted in said casing for transferring slides from said slide-storage container to the projecting position and returning the slides to the storage container, means operatively cooperating with said slide-changing mechanism and said slide-storage container held in position on said guideway for removing slides from one side of said dividing wall and for returning the slides after projection thereof to the other side of said dividing wall, said last-named means including a leaf spring secured to said dividing wall with its upper edge extending above the upper edge of the said wall thereby providing a guiding edge for said slide-changing mechanism, andresilient means on said slide-storage container for longitudinally displacing said container for a limited distance when a slide is being returned to the other side of said dividing wall after projection thereof.

4. A slide projector comprising a casing, means in said casing defining a guideway for a slide magazine, means on said guideway for holding in position thereon a slidestorage container wherein the slides are held against each other, there being a transverse dividing wall in the center of said slide-storage container, a reciprocating slide-changing mechanism mounted in said casing for transferring;

slides from said slide-storage container to the projecting position and returning the slides to the storage container, means operatively cooperating with said slide-changing mechanism and said slide-storage container held inposition on said guideway for removing slides from one side of said dividing wall and for returning the slides after projection thereof to the other side of said dividing wall, said last-named means including a leaf spring secured to said dividing wall with its upper edge extending above I the upper edge of the said wall thereby providing a guiding edge for said slide-changing mechanism, and resilient means on said slide-storage container for longitudinally displacing said container for a limited distance when a slide is being returned to the other side of said dividing wall after projection thereof, and rollers supporting said slide-storage container upon said guideway to facilitate the longitudinal displacement thereof.

5. A slide projector comprising a casing, means in said casingdefining a guideway for a slide magazine, means on said guideway for holding in position thereon a slidestorage container wherein the slides are held against each other, there being a transverse dividing wall in the center of said slide-storage container, a reciprocating slide-changing mechanism mounted in said casing for transferring slides from said slide-storage container to the projecting position and returning the slides to the storage container, means operatively cooperating with said slide-changing mechanism and said slide-storage containerheld in position on said guideway for removing slides from one side of said dividing wall and for returning the slides after projection thereof to the other side of said dividing wall, said last-named means including :a leaf spring secured 7 8 to said dividing wall with its upper edgeextendin g above References Cited by the Examiner the upper edge of the said wall thereby providing a guid- UNITED STATES PATENTS ing edge for said slide-changing mechanism, and resiiient means on said slide-storage container for urging the 5 lides on both sides of said dividing wall thereagainst "5 at 1m 6 s d d f 3,007,370 11/61 McMaster et al.

Sal 3,009,274 11/61 Kremp et a1, 4o 79 displacing said d1v1d1ng wall a l1m1ted distance longltudinally of said container when a slide is being returned to NORTON Pr'mary Exammer' the other side of said dividing wall after projection thereof. WILLIAM MISIEK, Examiner. 

2. A SLIDE PROEJCTOR COMPRISING A CASING, MEANS IN SAID CASING DEFINING A GUIDEWAY FOR A SLIDE MAGAZINE, MEANS ON SAID SAID GUIDEWAY FOR HOLDING IN POSITION THEREON A SLIDESTORAGE CONTAINER WHEREIN THE SLIDES ARE HELD AGAINST EACH OTHER, THERE BEING A TRANSVERSE DIVIDING WALL IN THE CENTER OF SAID SLIDE-STORAGE CONTAINER, A RECIPROCATING SLIDE-CHANGING MECHANISM MOUNTED IN SAID CASING FOR TRANSFERRING SLIDES FROM SAID SLIDE-STORAGE CONTAINER TO THE PROJECTING POSITION AND RETURNING THE SLIDES TO THE STORAGE CONTAINER, MEANS OPERATIVELY COOPERATING WITH SAID SLIDE-CHANGING MECHANISM AND SAID SLIDE-STORAGE CONTAINER HELD IN POSITION ON SAID GUIDEWAY FOR REMOVING SLIDES FROM ONE SIDE OF SAID DIVIDING WALL AND FOR RETURNING THE SLIDES AFTER PROJECTION THEREOF TO THE OTHER SIDE OF SAID DIVIDING WALL, SAID LAST-NEMED MEANS INCLUDING A LEAF SPRING SECURED TO SAID DIVIDING WALL WITH ITS UPPER EDGE EXTENDING ABOVE THE UPPER EDGE OF THE SAID WALL THEREBY PROVIDING A GUIDING EDGE FOR SAID SLIDE-CHANGING MECHANISM, AND RESILIENT MEANS ON SAID SLIDE-STORAGE CONTAINER FOR URGING THE SLIDES ON BOTH SIDES OF SAID DIVIDING WALL THERAGAINST. 